Emotional and cognitive characteristics were studied in epileptic patients before and following unilateral left or right temporal lobe resection. The integrity of attentional and perceptual (visual, auditory, and tactile) systems were evaluated using standard and experimental procedures. Physiological events (skin conductance) were also monitored during test performance. The research examined the role of the temporal lobe in establishing specific limbic associations between left and right hemispheres in regulating cognitive functions and emotional experiences in man. Tachistoscopic studies identified a critical perceptual role for right temporal mechanisms, especially during initial visual processing. The left and right temporal lobes contribute differentially to specifying the identity of a stimulus and its position or orientation in space. Left temporal mechanisms encode verbal information during initial learning. Modest compensation for memory defects following temporal lobectomy may be achieved with strategies which combine overt and covert imagery with praxic encoding. In affective sectors, left temporal patients tend to neutralize reactions to nuances with emotional coloration; right temporal patients, in contrast, rate these materials similar to normal individuals. Unlike normal individuals, however, the left and right temporal lobectomy patients were hyporesponsive to affective material as indexed by skin conductant measures. Moreover, both lobectomy groups failed to take advantage of the emotional characteristics of information to facilitate memory. These data suggest that unilateral temporal lobectomy disrupts the normal linkage of cognitive-affective associations mediated by temporal limbic interaction. There were, however, beneficial effects to surgical treatment in that patients, following temporal lobe surgery, were less deviant from normal subjects in emotional behavior.